Heretofore bottles and other portable containers for holding drinks have been provided with lids that are arranged to be opened to enable the user to have access to the contents of the bottle. Some of these prior art products have made use of self-opening lids, e.g., a lid which springs open when the lid is unlatched or actuated from its closed state. The means for opening such prior art lids have typically comprised either coil torsion springs, coil compression springs or elastomeric compression springs, which are arranged to operate to swing the lid from a closed state to an open state when the lid is unlatch or actuated. While each of those springs is generally suitable for effecting the opening of a lid for a bottle, vessel or other container, they never the less suffer from one or more disadvantages.
For example, insofar as coil torsion springs are concerned, they are typically unsanitary, since the coils can trap contaminants. In addition, they are difficult to assemble due to the fact that they are composed of multiple components. Further still, those coil torsion springs which can be made small enough to fit in the required size of bottle or container, have a tendency to fail due to fatigue.
Coil compression springs also suffer from the fact that they are not particularly sanitary due to the potential to trap contaminants in their coils. Moreover coil compression springs are also typically inserted into a pocket in the bottle or container, thereby resulting in another area that may trap contaminants. Like coil torsion springs, coil compression springs are difficult to assembly due to their multiple components. Lastly coil compression having a controlled variable spring rate are expensive.
Elastomeric compression springs also suffer from the disadvantage of not being sanitary. In this regard, such springs, like coil compression springs, are typically mounted or inserted into a pocket, which can serve as a trap for contamination. Moreover, the spring's pocket also traps air that can push spring out. If the assembly is vented to prevent the trapping of air, such an arrangement increases contamination hazard because the vent allows for flow between the pocket and container, but not enough to properly clean. Moreover, elastomeric compression springs, if biased so that they will not over-compress may not be able to store enough energy to open the lid, when required. In this regard, in order to store enough energy to effectively open the lid, the spring needs to have a high spring rate, thus rendering it susceptible to compression set, or it may be too long to fit in the available confined space within the lid. Lastly, the tolerances in the manufacture of elastomeric compression springs make it difficult, if not impossible, to control a force high enough to open the lid, but not so high as to produce an abrupt or jarring effect when the lid reaches the end of its swing.
Accordingly, a need exists for a self-opening lid for a bottle or for any other container having an interior which is to be closed off by the lid, and which overcomes the disadvantages of the prior art.
The subject invention addresses those needs by providing a self-opening hinged lid exhibiting a pleasing tactile experience, and which does not add exorbitant cost to the product in which it is located.